Pharmaceutical formulation comprising ciclesonide

ABSTRACT

The disclosure relates to the field of medicine, in particular to the field of veterinary medicine. The disclosure relates to a pharmaceutical (medicament) formulation of glucocorticoids, especially ciclesonide or a pharmaceutically acceptable derivative thereof.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.14/132,578, filed Dec. 18, 2013, which claims priority from EuropeanPatent Application No. 12199302.6, filed Dec. 21, 2012, and fromEuropean Patent Application No. 13190393.2, filed Oct. 25, 2013, thedisclosures of which are all incorporated herein by reference in theirentireties.

FIELD OF THE INVENTION

The invention relates to pharmaceutical formulations of the activesubstance ciclesonide, des-ciclesonide or a pharmaceutically acceptablederivative thereof, in particular for the field of veterinary medicine,more particularly for the field of equine medicine. The inventionfurther relates to methods of preparing a pharmaceutical formulationcomprising ciclesonide, des-ciclesonide or a pharmaceutically acceptablederivative thereof as well as an inhalation kit.

BACKGROUND INFORMATION

Due to the low water solubility of glucocorticoids, they are normallyformulated as a solid for oral or inhalative application. Examplesinclude orally administered tablets for prednisolone or a powderformulation for inhalation out of a dry powder inhaler (DPI) forbudesonide. However, oral dosage forms of glucocorticoids have thedisadvantage of frequent side effects especially after long-term use.Furthermore, the DPI inhaler type is acceptable for humans who canregulate their breathing to breath in the powder through the mouthpieceof an inhaler. Animals, however, cannot use such an inhaler sincebreathing cannot be coordinated to inhale a powder out of a DPI. Forapplication to animals a pressurized multi-dose inhaler (pMDI) or anaqueous/ethanolic droplet inhaler (would be more suitable, as the liquidformulation in such inhalers is aerosolized by an energy source such asa refrigerant or a spring. It is possible to formulate a glucocorticoidfor a pMDI or an aqueous/ethanolic droplet inhaler by producing asolution with a pharmaceutically acceptable co-solvent such as ethanol.Such a formulation for use in a pMDI is ALVESCO® for human use. Theformulation of ALVESCO® is a solution of ciclesonide in a mixture ofethanol and refrigerant (hydrofluoroalkanes). However, the use ofhydrofluoroalkanes as a refrigerant has disadvantages.Hydrofluoroalkanes have been found to degrade ozone in the atmosphere.Hence, it would be desirable to develop a formulation of aglucocorticoid that can be aerosolized but does not contain ahydrofluoroalkane.

BRIEF SUMMARY OF THE INVENTION

The present invention concerns a pharmaceutical (medicament) formulationcomprising or containing as active substance one or more compounds ofthe formula I or II, preferably formula I, most preferably theR-enantiomer of formula I

-   -   optionally in the form of the tautomers, enantiomers, mixtures        of the enantiomers, racemates, solvates or hydrates thereof,    -   at least one pharmacologically acceptable acid,    -   optionally further pharmacologically acceptable excipients        and/or solvents,    -   whereby said formulation is preferably a liquid formulation        containing as solvent ethanol or a mixture of water and ethanol,        preferably an ethanolic solution for inhalation, preferably for        veterinary use, preferably with an (equine) inhaler device.        “Ethanolic” in this context refers to mixtures of ethanol and        water as well as pure ethanol.        The invention concerns a pharmaceutical (medicament) formulation        comprising or containing as active substance ciclesonide or a        pharmaceutically acceptable salt thereof, preferably in the        R-enantiomer form.

The pH value of an aqueous solution is defined as −log₁₀ [H⁺], where[H⁺] represents the activity of hydrogen ions which corresponds to themolar concentration in diluted solutions. The pH value of an ethanolicliquid formulation is not clearly defined. For this reason an “apparent”pH value for ethanolic solutions is defined in the present invention aspH_(app)=−log₁₀[H+]. The value of pH_(app) and the concentration ofhydrogen ions, [H⁺], which reflects ionic strength, are inverselycorrelated. High pH_(app) value ⇔ low value for [H⁺]. In this textpH_(app) refers to −log₁₀[H⁺] and not to the value that is measured witha pH electrode such as for aqueous solutions.

For ethanolic formulations of ciclesonide it has been surprisingly foundto be advantageous to set pH_(app) in the range of 4.0 to 4.6. Toidentify an appropriate pH_(app) in an ethanolic liquid formulationcomprising ciclesonide is a challenge. On the one hand side thestability of ciclesonide is better at higher (more neutral) pH values.However, on the other hand, the pH should not be too high since at low[H⁺] values already small amounts of contaminants and decompositionproducts can cause a relatively large change in pH_(app). Furthermore,the use of a buffer for inhalable formulations is undesirable due to theadministration of the buffer constituents to the lungs and thepossibility of the buffer constituents forming a residue in the inhalerwhich may affect the spray characteristics of the aerosol. Surprisingly,the pH_(app) range of 4.0 to 4.6 allows for an ethanolic formulation ofciclesonide where ciclesonide is chemically stable and the pH_(app)value remains stable. The addition of buffer is not necessary to createthe advantageous formulation of the present invention.

According to a specific aspect of the present invention said formulationis a solution for inhalation. Equivalent terms are inhalable formulationor a formulation in the form of an inhalant. In another aspect of thepresent invention the formulation is in a liquid formulation, preferablyan ethanolic formulation, which can be aerosolized to facilitate itsinhalation. In a further aspect the liquid formulation is partiallyethanolic and partially aqueous. In a further aspect of the presentinvention the liquid formulation comprises one or more of the solventswater, ethanol, and optionally additional excipients.

In a preferred aspect of the present invention the liquid formulationcomprises a mixture of water and ethanol, e.g. 10% V/V aqueous and 90%V/V ethanolic.

In a further preferred aspect of the present invention the solvent ofthe liquid formulation comprises a mixture of ethanol and water, wherebythe proportion of ethanol is in the range of 85-100% V/V, preferably90-95% V/V. Preferably the proportion of ethanol is 90% V/V ethanol.

In a specific aspect of the present invention the formulation (solutionfor inhalation) of ciclesonide is as follows:

TABLE 1 concentration Ingredient [g/100 mL] Ciclesonide 3.0 HCl 0.1 M[mL] 0.0424 [H⁺] [μmol/L ] 31.6 pH_(app) 4.5 Mass ethanol [g] 68.8 Masswater [g] 11.5

For the solution listed in the Table 1 above the density was found to be0.83 g/mL. More HCl is added than needed to achieve −log[H⁺]=31.6 μmol/Lin demineralized water alone due to the buffering capacity ofciclesonide. It was found that this buffering capacity=−3.6 μmol/gciclesonide, i.e. for 3.0 g of ciclesonide 10.8 μmol/L extra [H⁺] needsto be added to reach the value of 31.6 μmol/L. That means that theamount of HCl (0.1 M) needed for 100 mL to achieve pH_(app)=4.5 is0.0316 mL+0.0108 mL=0.0424 mL.

In another specific aspect of the present invention the formulation(solution for inhalation) of ciclesonide is as follows:

TABLE 2 Ingredient Content Ciclesonide 0.7 − 3.1 g/100 mL Hydrochloricacid ad [H⁺] = 10^(−3.5) to 10⁻⁵ mol/L 90% V/V ad 100 mL ethanol/waterwhere the concentration of hydrogen ions [H⁺] can be measured, forexample, by potentiometric titration.

A further aspect of the present invention is the application of theliquid formulation according to the present invention using an inhalerdevice, such as the RESPIMAT® inhaler or another inhaler using theRESPIMAT® aerosol-generating technology. The RESPIMAT® inhaler isdisclosed for example in WO 97/12687, which is hereby incorporated byreference. Although this inhaler is presently marketed by BoehringerIngelheim for human application as an aqueous droplet inhaler for usewith aqueous solutions (SPIRIVA® RESPIMAT®, COMBIVENT® RESPIMAT®,BERODUAL® RESPIMAT®), this inhaler can advantageously be used to producethe inhalable aerosols/inhalants of ethanolic solutions according to theinvention. The dose of active substance delivered ex RESPIMAT® inhalercan be calculated from:

-   -   the concentration of active substance in the liquid formulation        (solution for inhalation) [μg/μL],    -   the “delivered volume”, defined as the volume of liquid expelled        from the RESPIMAT® inhaler per actuation [μL]. The delivered        volume ex RESPIMAT® inhaler has been found to be approximately        11 μL per actuation,        according to the following formula:        Dose [μg]=Concentration [μg/μL]·Delivered Volume [μL]

In a specific aspect of the present invention the pharmaceutical(medicament) formulation is administered via an inhaler device to apatient, preferably to an equine patient, most preferably to a horse.For the application in horses high doses and thus highly concentratedformulations are a prerequisite. Due to the low solubility ofciclesonide especially in water as well as the low chemical stability ofciclesonide at certain pH_(app) values this is a challenge, especiallyin an ethanolic formulation.

Preferably said inhaler device comprises: (a) an aqueous/ethanolicdroplet inhaler such as the RESPIMAT® inhaler or another inhaler usingthe RESPIMAT® aerosol-generating technology and (b) an adapter forequine use. In another specific aspect of the present invention thepharmaceutical (medicament) formulation is a partially/mainly ethanolicformulation and is administered via an (equine) inhaler device.

The invention further concerns a method for preparing a pharmaceutical(medicament) formulation according to the present inventioncharacterized by the addition of a fixed amount of hydrochloride acid tothe formulation in the production process. For formulations specified tohave a certain pH value, according to the prior art the acid is normallyslowly added (titrated) to the solution until the target pH value asmeasured by a pH electrode is reached. The process of the presentinvention is simpler since a fixed amount of a strongly dissociated acid(e.g. HCl) is added to the production vessel and no titration isnecessary. The concentration of H⁺ ions [H⁺] can be checked, ifnecessary, using potentiometric titration.

The invention further concerns product produced by the above process aswell as an inhalation kit consisting of or comprising a pharmaceutical(medicament) formulation according to the present invention, an (equine)inhaler device, preferably an aqueous/ethanolic droplet inhaler such asthe RESPIMAT® inhaler or another inhaler using the RESPIMAT®aerosol-generating technology suitable for nebulizing thispharmaceutical (medicament) formulation, optionally an adapter forequine use, and optionally an instruction leaflet (enclosed label) orinformation and direction for use.

DETAILED DESCRIPTION OF THE INVENTION

Before describing the various aspects of the present invention it shallbe noted that as used herein and in the appended claims, the singularforms “a”, “an”, and “the” include plural reference unless the contextclearly dictates otherwise. Thus, for example, reference to “apreparation” includes a plurality of such preparations reference to the“carrier” is a reference to one or more carriers and equivalents thereofknown to those skilled in the art, and so forth. Unless definedotherwise, all technical and scientific terms used herein have the samemeanings as commonly understood by one of ordinary skill in the art towhich this invention belongs. All given ranges and values may vary by 1to 5% unless indicated otherwise or known otherwise by the personskilled in the art, therefore, the term “about” was omitted from thedescription. Although any methods and materials similar or equivalent tothose described herein can be used in the practice or testing of thepresent invention, the preferred methods, devices, and materials are nowdescribed. All publications mentioned herein are incorporated herein byreference for the purpose of describing and disclosing the substances,excipients, carriers, and methodologies as reported in the publicationswhich might be used in connection with the invention. Nothing herein isto be construed as an admission that the invention is not entitled toantedate such disclosure by virtue of prior invention. Terms notspecifically defined herein should be given the meanings that would begiven to them by one of skill in the art in light of the disclosure andthe context. As used in the specification, however, unless specified tothe contrary, the following terms have the meaning indicated and thefollowing conventions are adhered to.

The term “ciclesonide”((11β,16α)-16,17-[[(R)-Cyclohexylmethylene]bis(oxy)]-11-hydroxy-21-(2-methyl-1-oxopropoxy)pregna-1,4-diene-3,20-dione,C₃₂H₄₄O₇, M_(r)=540.7 g/mol) is well known in the art andmeans/describes a glucocorticoid used to treat asthma and allergicrhinitis in humans. It is marketed for application in humans under thebrand name ALVESCO® for asthma and OMNARIS®/OMNIAIR® for hay fever inthe US and Canada. Ciclesonide is a prodrug. It is transformed into theactive metabolite C21-C21-desisobutyrylciclesonide (=des-ciclesonide)via hydrolysis by intracellular esterases in the lung. Ciclesonide is anon-halogenated glucocorticoid, which predominantly exists in the formof an R-Enantiomer.

The prodrug nature of ciclesonide is an advantage for the pharmaceutical(medicament) formulation according to the present invention. It has beenshown that the active metabolite (C21-C21-des-isobutyrylciclesonide) isgenerated only in the airways of humans or other mammals such asequines. The prodrug ciclesonide has to be activated by special enzymesin the airway tissues in order to generateC21-C21-des-isobutyrylciclesonide, which is the effective molecule.

Therefore, even if large amounts of ciclesonide are swallowed duringaerosol treatment the prodrug nature of ciclesonide and the dependencyon specific enzyme conversion in the lung for generation of the activecompound C21-C21-des-isobutyrylciclesonide assures that the effect ofciclesonide is only related to the airways and not to the whole body ofthe horses. This is also referred to as a topical effect of ciclesonide.In contrast, the state of the art treatment with dexamethasone or othersubstances like fluticasone leads to a systemic exposure of the activemetabolite, leading to an extensive side effect profile whenadministrating these other formulations of the prior art, for exampleDEXABENE® for dexamethasone dihydrogenphosphate disodium as an injectionsolution; or VIANI® DISCUS® for fluticasone propionate or PULMICORT®TURBOHALER® for budesonide) as powders for inhalation).

The term “dexamethasone” is well known in the art and means/describes apotent synthetic member of the glucocorticoid class of steroid drugs. Itacts as an anti-inflammatory and immunosuppressant. When taken orally,it is 27 times more potent than the naturally occurring hormone cortisoland 7 times more potent than prednisone.

As used herein the term “prodrug” refers to (i) an inactive form of adrug that exerts its effects after metabolic processes within the bodyconverting it to a usable or active form, or (ii) a substance that givesrise to a pharmacologically active metabolite, although not itselfactive (i.e. an inactive precursor).

The terms “prodrug” or “prodrug derivative” mean a covalently-bondedderivative, carrier or precursor of the parent compound or active drugsubstance which undergoes at least some biotransformation prior toexhibiting its pharmacological effect(s). Such prodrugs either havemetabolically cleavable or otherwise convertible groups and are rapidlytransformed in vivo to yield the parent compound, for example, byhydrolysis in blood or by activation via oxidation as in the case ofthioether groups. Most common prodrugs include esters and amide analogsof the parent compounds. The prodrug is formulated with the objectivesof improved chemical stability, improved patient acceptance andcompliance, improved bioavailability, prolonged duration of action,improved organ selectivity, improved formulation (e.g., increasedhydrosolubility), and/or decreased side effects (e.g., toxicity). Ingeneral, prodrugs themselves have weak or no biological activity and arestable under ordinary conditions. Prodrugs can usually be readilyprepared from the parent compounds using methods known in the art.

The term “equine” means of or belonging to the family Equidae, whichincludes the horses, asses, and zebras, preferably horses. In addition,the term “equine” encompasses also hybrids of members of the familyEquidae (e.g. mules, hinnies, etc.).

The term “patient” or “subject” embraces mammals such as primatesincluding humans. The term “patient” or “subject” as used herein relatesspecifically to equines such as horses, especially horses suffering fromairway disease (particularly pulmonary disease).

The term “pharmaceutically acceptable derivative thereof” means but isnot limited to pharmaceutically acceptable salts, derivatives,metabolites or pro-drugs of a drug. Derivatives as used herein includebut are not limited to, any hydrate forms, solvates, isomers,enantiomers, racemates, racemic conglomerate and the like of thecompound of choice. Suitable pharmaceutically acceptable salts are wellknown in the art and may be formed with an inorganic or organic acid,such as hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoricacid, nitric acid, acetic acid, glycolic acid, lactic acid, pyruvicacid, malonic acid, succinic acid, glutaric acid, fumaric acid, malicacid, mandelic acid, tartaric acid, citric acid, ascorbic acid, palmiticacid, maleic acid, hydroxymaleic acid, benzoic acid, hydroxybenzoicacid, phenylacetic acid, cinnamic acid, salicylic acid, methanesulfonicacid, benzenesulfonic acid and toluenesulfonic acid.

The term “pharmaceutical (medicament) formulation or solution” meansnon-pressurized metered-dose preparations for inhalation, which aresolutions, suspensions or emulsions for use with inhalers that convertliquids into aerosols using single or multiple liquid jets, ultrasonicvibration or other methods. The volume of liquid to be converted into anaerosol is pre-metered or metered by the inhaler so that the dosedelivered from the inhaler can be inhaled with 1 or more inspirations.

Administration

Suitable forms for “administration” are for example inhalation,parenteral or oral administration.

In the specific administration via the RESPIMAT® inhaler the content ofthe pharmaceutically effective ciclesonide should be in the range from0.1 to 5% m/V, preferably 0.7 to 3.1% m/V or 1.0 to 3.1% m/V of thetotal composition, i.e. in amounts which are sufficient to achieve thedose range specified hereinafter.

When administered by inhalation ciclesonide may be given as an ethanolicsolution or a solution containing a mixture of water and ethanol.Preferably, therefore, pharmaceutical formulations are characterized inthat they comprise ciclesonide according to the preferred aspects above.

It is particularly preferred that ciclesonide is administered viainhalation/ex inhaler, preferably it is administered once or twice aday. Suitable formulations may be obtained, for example, by mixingciclesonide with known excipients, for example water, pharmaceuticallyacceptable organic solvents such as mono- or polyfunctional alcohols(e.g. ethanol or glycerol). For a liquid formulation, additionalexcipients for example hydrochloric acid or citric acid to adjust the[H⁺] concentration may be added.

It is especially preferred that ciclesonide is administered by/via anaqueous/ethanolic droplet inhaler, for example the RESPIMAT® inhaler oranother inhalation device using the RESPIMAT® aerosol-generatingtechnology. Preferably, the pharmaceutical formulation comprisingciclesonide is administered once or twice a day. For this purpose,ciclesonide has to be made available in a liquid solution which issuitable for the inhaler.

Preferably the solvent in the liquid formulation (inhalation solution)comprises a mixture of water and ethanol, such as 10% V/V aqueous and90% V/V ethanolic. In a further aspect of the present invention thesolvent in the liquid formulation (inhalation solution) comprises amixture of ≥85% V/V ethanol and ≤15% V/V water, such as 90% V/V ethanoland 10% V/V water.

In a further preferred aspect of the present invention the solvent inthe liquid formulation (inhalation solution) comprises a mixture ofethanol and water, whereby the proportion of ethanol is in the range of85-100% V/V, preferably 90-95% V/V. Preferably the proportion of ethanolis 90% V/V ethanol.

In a specific embodiment the formulation of ciclesonide is as follows:

TABLE 3 Ingredient Content Ciclesonide 0.7 − 3.1 g/100 mL Hydrochloricad [H⁺]= 10^(−3.5) to acid 10⁻⁵ mol/L 90% V/V ad 100 mL ethanol/waterwhere the concentration of hydrogen ions [H⁺] can be measured, forexample, by potentiometric titration.

A further aspect of the present invention is the application of theliquid formulation (inhalation solution) using the RESPIMAT® inhaler oranother inhalation device based on the RESPIMAT® aerosol-generatingtechnology. This inhaler is disclosed for example in WO 97/12687, whichis hereby incorporated therein. This inhaler can advantageously be usedto produce the inhalable aerosols according to the invention. The doseof active substance delivered ex RESPIMAT® inhaler can be calculatedfrom:

-   -   the concentration of active substance in the liquid formulation        [μg/μL],    -   the “delivered volume”, defined as the volume of liquid expelled        from the RESPIMAT® inhaler per actuation [4]. The delivered        volume ex RESPIMAT® inhaler has been found to be approximately        11 μL per actuation,        according to the following formula:        Dose [μg]=Concentration [μg/μL]·Delivered Volume [μL]

In a further aspect of the present invention the composition isadministered via an (equine) inhaler device. The (equine) inhaler devicepreferably comprises/consists of the RESPIMAT® inhaler or anotherinhaler using the RESPIMAT® aerosol-generating technology, and otherparts to adapt the inhaler to equine use. In a preferred aspect thecomposition is a partially ethanolic formulation and is administered viaan (equine) inhaler device. The dose emitted via the (equine) inhalerdevice can be slightly lower than the dose ex RESPIMAT® inhaler.

The RESPIMAT® inhaler is one specific form of an aqueous/ethanolicdroplet inhaler. Other aqueous/ethanolic droplet inhalers may be used.

The concentration of ciclesonide contained in the solution in theinhalation device ranges preferably from 0.7 to 5% m/V or 0.7 to 3.1%m/V.

The present invention concerns a pharmaceutical (medicament) formulationcomprising/containing ciclesonide and/or des-ciclesonide as activesubstance, optionally in the form of the tautomers, enantiomers,mixtures of the enantiomers, racemates, solvates or hydrates thereof, atleast one pharmacologically acceptable acid, optionally furtherpharmacologically acceptable excipients and/or solvents, whereby saidformulation is an ethanolic solution or a solution containing a mixtureof ethanol and water.

In a specific aspect of the present invention the proportion of ethanolin the (solvent consisting of a) mixture of ethanol and water is in therange of 85-100% V/V, preferably 90-95% V/V, most preferably 90% V/V.Further preferred is a proportion of ethanol ≥85% V/V ethanol,preferably ≥90% V/V ethanol.

In a specific aspect of the present invention said formulation is asolution for inhalation.

In a further specific aspect of the present invention the −log₁₀[H+] ofsaid formulation is in the range of 4.0 to 4.6.

In a specific aspect of the present invention one (the) active substanceis ciclesonide or a pharmaceutically acceptable salt thereof, preferablyin the R-enantiomer form, preferably at a concentration of 0.1-5 g/100mL, preferably 0.7-3.1 g/100 mL, most preferably at a concentration of 3g/100 mL.

In another specific aspect of the present invention thepharmacologically acceptable excipient and/or solvent comprises (i) oneor more of the following excipients and/or solvents selected from thegroup consisting of: water, a pharmaceutically acceptable organicsolvent such as mono- or polyfunctional alcohol (e.g. glycerol orpropanol), and (ii) optionally additional excipients and/or solvents.

In a further aspect of the present invention the pharmacologicallyacceptable acid is selected from the inorganic acids hydrochloric acid,phosphoric acid, hydrobromic acid, nitric acid and sulfuric acid or fromthe organic acids citric acid, tartaric acid, malic acid, maleic acid,succinic acid, fumaric acid, acetic acid, formic acid, propionic acid,sorbic acid, benzoic acid, methanesulfonic acid and benzenesulfonicacid, preferably the acid is hydrochloric acid.

In a preferred aspect of the present invention the pharmacologicallyacceptable acid is selected from the inorganic acids hydrochloric acid,phosphoric acid, and hydrobromic acid.

In a specific aspect of the present invention the formulation isadministered via an (equine) inhaler device.

The invention further concerns a method of preparing a pharmaceutical(medicament) formulation according to the present invention comprisingthe following steps:

-   -   (a) Dissolving ciclesonide in a solvent comprising ethanol and        water,    -   (b) Adding a fixed amount of acid, preferably hydrochloric acid        (HCl), most preferably as a 0.1 or 1.0 molar solution. As a        result thereof −log₁₀[H+] is in the preferable range of 4.0 to        4.6.

The invention further concerns a method of preparing a pharmaceutical(medicament) formulation according to the present invention comprisingthe following steps:

-   -   (a) Dissolving ciclesonide in a solvent comprising ethanol and        water,    -   (b) Adding a fixed amount of acid, preferably hydrochloric acid        (HCl), most preferably as a 0.1 or 1.0 molar solution, to reach        a value of −log₁₀[H⁺]=4.0 to 4.6

In a specific aspect of the method according to the present inventionthe proportion of ethanol in the solvent of step (a) is in the range of85-100% V/V, preferably 90-95% V/V, and most preferably the proportionof ethanol in the solvent of step (a) is 90% V/V ethanol.

Preferably ciclesonide is first dissolved in ethanol. This can be doneby either adding ciclesonide to ethanol in a vessel or first weighingthe appropriate amount of ciclesonide into the vessel and then addingethanol. The amount of water needed to reach the target solventcomposition is then added. Therefore, in a specific aspect of thepresent invention ciclesonide is first dissolved in ethanol and theamount of water needed to reach the target solvent composition is thenadded.

In a further specific aspect of the method according to the presentinvention the method comprises the additional steps:

-   -   (c) Mixing until a homogenous solution is formed,    -   (d) Optionally filtering the solution, preferably through one or        more filters with a pore size of maximum 1.0 μm for at least one        of the filters, most preferably of maximum 0.2 μm,    -   (e) Optionally filling the solution into containers.

Said containers are preferably appropriate for long-term storage and/orfor use with the appropriate inhaler device (such as e.g. the RESPIMAT®inhaler or another inhaler using the RESPIMAT® aerosol-generatingtechnology).

In a specific aspect of the present invention the inhaler device is anequine inhaler device, which preferably comprises/consists of theRESPIMAT® inhaler or another inhaler using the RESPIMAT®aerosol-generating technology, and other parts to adapt the inhaler toequine use.

The present invention further concerns a pharmaceutical (medicament)formulation comprising/containing ciclesonide as active substanceobtainable/obtained/prepared by a method according to the presentinvention.

The present invention further concerns an inhalation kitcomprising/consisting of a pharmaceutical (medicament) formulationaccording to the present invention, an (equine) inhaler device,preferably a pressurized metered dose inhaler or an aqueous/ethanolicdroplet inhaler such as the RESPIMAT® inhaler or another inhaler usingthe RESPIMAT® aerosol-generating technology, suitable for nebulizingthis pharmaceutical (medicament) formulation, optionally an adapter forequine use, and optionally an instruction leaflet (enclosed label) orinformation and direction for use.

EXAMPLES

The following examples serve to further illustrate the presentinvention; but the same should not be construed as a limitation of thescope of the invention disclosed herein.

Example 1 (Ciclesonide Formulations)

Ciclesonide monopreparation is formulated as a solution for inhalationas follows:

TABLE 4 concentration Ingredient [g/100 mL] Ciclesonide 3.0 HCl 0,1 M[mL] 0.0424 c H⁺ [μmol/L] 31.6 pH_(app) 4.5 Mass Ethanol [g] 68.8 MassWaster [g] 11.5The measured density of the above solution at 20° C. is 0.83 g/mL.

Another ciclesonide monopreparation is formulated as a solution forinhalation as follows:

TABLE 5 Ingredient Content Ciclesonide 0.7 − 3.1 g/100 mL Hydrochloricacid ad [H⁺] = 10^(−3.5) to 10⁻⁵ mol/L 90% V/V ad 100 mL ethanol/water

-   -   where the concentration of hydrogen ions [H⁺] can be measured,        for example, by potentiometric titration.

Example 2 (Method for Preparing Ciclesonide Formulation)

A ciclesonide formulation (solution for inhalation) is prepared asfollows:

-   -   1. 30 g Ciclesonide is weighed into a 2 L vessel    -   2. 687.5 g Ethanol (>99.9% purity) is added. The mixture is        stirred until the ciclesonide dissolves and a homogeneous        solution is formed.    -   3. 114.7 g Purified water is slowly added. The mixture is        stirred until a homogeneous solution is formed.    -   4. 0.424 mL Hydrochloric acid (0.1M) is added. The mixture is        stirred until a homogeneous solution is formed.    -   5. The resulting solution is filtered through a membrane filter        with a 0.2 μm pore size using nitrogen pressure.    -   6. The filtered solution is filled into cartridges suitable for        the RESPIMAT® inhaler.

The defined volume of HCl surprisingly shows a good correlation betweenpH_(app) (target) and pH_(app) (titration).

The invention claimed is:
 1. A method of preparing a pharmaceuticalformulation, comprising the following steps: dissolving ciclesonide in asolvent comprising ethanol and water to form a solution; and adding afixed amount of a pharmaceutically acceptable acid at 0.1 or 1.0 molarto reach a value of −log₁₀[H+] in the range of 4.0 to 4.6 for thesolution wherein the acid comprises hydrochloric acid (HCl).
 2. Themethod of claim 1, wherein a proportion of ethanol in the solvent is ina range of 85-100% V/V.
 3. The method of claim 1, wherein a proportionof ethanol in the solvent is in a range of 90-95% V/V.
 4. The method ofclaim 1, wherein a proportion of ethanol in the solvent is 90% V/Vethanol.
 5. The method of claim 1, wherein ciclesonide is firstdissolved in ethanol and an amount of water needed to reach a targetsolvent composition for the solution is then added.
 6. The method ofclaim 1, further comprising: mixing until a homogeneous solution isformed.
 7. The method of claim 1, further comprising: filtering thesolution through one or more filters with a pore size of maximum 1.0 μmfor at least one of the filters.
 8. The method of claim 7, wherein saidpore size maximum for at least one of the filters is 0.2 μm.
 9. Themethod of claim 1, further comprising: filling the solution intocontainers appropriate for long term storage and for use with aninhaler.
 10. The method of claim 1, wherein ciclesonide is dissolved inthe solvent in a sufficient amount such that the formulation includesciclesonide at a concentration of 0.7 g/100 mL to 5 g/100 mL.
 11. Themethod of claim 1, wherein ciclesonide is dissolved in the solvent in asufficient amount such that the formulation includes ciclesonide at aconcentration of 0.7 g/100 mL to 3.1 g/100 mL.
 12. The method of claim1, wherein ciclesonide is dissolved in the solvent in a sufficientamount such that the formulation includes ciclesonide at a concentrationof 3 g/100 mL.